A prosthesis or implant can be positioned in an anatomy, such as a human patient, for various purposes. For example, a prosthesis can be positioned to replace an articulating portion of an anatomy. An incorrectly installed stem can result in an incorrectly placed prosthesis. An incorrectly placed prosthesis can result in pain, limit range of motion, increase wear debris, limit joint stability, and decrease the lifespan of the prosthesis.